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arXiv · 1308.0905

Shaping the evanescent field of optical nanofibers for cold atom trapping

C. F. Phelan·T. Hennessy·Th. Busch
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Abstract

We investigate trapping geometries for cold, neutral atoms that can be created in the evanescent field of a tapered optical fibre by combining the fundamental mode with one of the next lowest possible modes, namely the HE21 mode. Counter propagating red-detuned HE21 modes are combined with a blue-detuned HE11 fundamental mode to form a potential in the shape of four intertwined spirals. By changing the polar- ization from circular to linear in each of the two counter-propagating HE21 modes simultaneously the 4-helix configuration can be transformed into a lattice configuration. The modification to the 4-helix configuration due to unwanted excitation of the the T E01 and T M01 modes is also discussed.

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C. F. Phelan, T. Hennessy, Th. Busch. 2013-08-05. Shaping the evanescent field of optical nanofibers for cold atom trapping. https://doi.org/10.1364/oe.21.027093

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